Method for use in transmitting signal, terminal device, and network device

ABSTRACT

Disclosed is a method for use in transmitting a signal, a terminal device, and a network device. The method includes: a terminal device receives a signal transmitted by a network device employing multiple downlink transmission beam groups; and the terminal device transmits first information to the network device, thus allowing the network device to determine a first downlink transmission beam group from the multiple downlink transmission beam groups, and at least one downlink transmission beam group of the multiple downlink transmission beam groups comprising multiple downlink transmission beams.

CROSS REFERENCE TO RELATED APPLICATION

This application is a continuation of U.S. application Ser. No.16/483,418, filed Aug. 3, 2019, which is a U.S. national phaseapplication of International Application No. PCT/CN2017/073002, filedFeb. 6, 2017, the entire disclosures of which are incorporated herein byreference.

TECHNICAL FIELD

The embodiments of the present application relate to the communicationfield, and more particularly, to a method, a terminal device, and anetwork device for transmitting a signal.

BACKGROUND

In a multi-beam system, a terminal device and a network device may traina plurality of beams by beamforming, and different beams may correspondto different directions and different coverage areas. Generally, thenetwork device does not know performance of downlink transmission beams,and uses all downlink transmission beams in a system to send signals tothe terminal device, resulting in a large system signaling overhead.

SUMMARY

In view of this, the embodiments of the present application provide amethod, a terminal device, and a network device for transmitting asignal, which can reduce system signaling overhead.

In a first aspect, there is provided a method for transmitting a signal,including: receiving, by a terminal device, a signal sent by a networkdevice by using a plurality of downlink transmission beam groups; andsending, by the terminal device, first information to the networkdevice, so that the network device determines a first downlinktransmission beam group from the plurality of downlink transmission beamgroups, at least one of the plurality of downlink transmission beamgroups including a plurality of downlink transmission beams.

Each downlink transmission beam group includes at least one downlinktransmission beam. The first information may be an implicit indicationor an explicit indication, the explicit indication may be indicated byseveral bits, and the implicit indication may make the downlinktransmission beam groups correspond to transmission characteristics andfeed back to the network device through a certain transmissioncharacteristic.

In addition, a beam is physically invisible with respect to the terminaldevice in a system. After receiving the signal sent by the networkdevice by a plurality of beams, the terminal device may identifydifference of the beams by using difference of the signals. That is tosay, the terminal device may feed back to the network device by usingthe transmission characteristic indicated by a certain signal, and thenetwork device may determine the downlink transmission beam in whichgroup is preferable according to the transmission characteristic fedback by the terminal device.

When there are a plurality of downlink transmission beams, the downlinktransmission beams are grouped by the transmission characteristic, andafter receiving the signals sent by the plurality of downlinktransmission beams, the terminal device may select a signal with bettertransmission characteristic and notify the network device of thetransmission characteristic adopted by the signal. After receiving thetransmission characteristic, the network device may determine thecorresponding downlink transmission beam group, so that the networkdevice only uses this part of the beams to perform signal transmissionlater, thereby reducing the system signaling overhead.

In a possible implementation manner, the first information is a randomaccess preamble sequence, and the random access preamble sequence and/ora physical random access channel resource used to send the random accesspreamble sequence correspond to the first downlink transmission beamgroup.

By corresponding the random access preamble sequence and/or the physicalrandom access channel resource to the downlink transmission beam group,a partition granularity of the random access preamble sequence and/orthe physical random access channel resource of each group is relativelylarge, thereby reducing a collision probability of random access.

The first downlink transmission beam group is indicated to the networkdevice by using the first information, which may be directly indicatedby the first information, or may be indicated by other transmissioncharacteristic of the first information, such as occupied frequencydomain resource and/or time domain resource.

In a possible implementation manner, after the terminal device sends thefirst information to the network device, the method further includes:sending, by the terminal device, second information to the networkdevice, so that the network device determines a first downlinktransmission beam from the plurality of downlink transmission beamgroups, the first downlink transmission beam being a downlinktransmission beam that is expected by the terminal device for thenetwork device to transmit a subsequent signal.

In a possible implementation manner, the first downlink transmissionbeam is a beam in the first downlink transmission beam group.

Optionally, the fed back first downlink transmission beam may be a beamwith the best transmission performance selected by the terminal device.

Optionally, the first downlink transmission beam may not belong to thefirst downlink transmission beam group. For example, after indicatingthe first downlink transmission beam group to the network device, theterminal device finds that the beam with the best performance belongs toother group, and then the terminal device may directly feed back thefirst downlink transmission beam to the network device.

A two-step indication method is used to feed back the downlinktransmission beam expected by the terminal device to the network device,which can greatly reduce the signaling overhead. Moreover, by the mannerin which the random access preamble sequence and/or physical randomaccess channel resource directly indicate the beam group, the collisionprobability of random access may be reduced.

In a possible implementation manner, before the terminal device sendsthe second information to the network device, the method furtherincludes: receiving, by the terminal device, third information sent bythe network device, the third information being used to indicate whetherthe terminal device needs to send the second information to the networkdevice; and according to the third information, determining, by theterminal device, whether to send the second information to the networkdevice.

Further, the third information is carried in a random access responsemessage sent by the network device to the terminal device, and/or thesecond information is carried in a message used to send an identifier ofthe terminal device in a random access process.

In a possible implementation manner, the second information is anidentifier of a signal carried on the first downlink transmission beamreceived by the terminal device, and the signal carried on the firstdownlink transmission beam is at least one of following signals: aprimary synchronization signal, a secondary synchronization signal, abroadcast signal, a reference signal, and a signal carrying a systemmessage.

In a second aspect, there is provided a method for transmitting asignal, including: sending, by a network device, a signal to a terminaldevice by using a plurality of downlink transmission beam groups;receiving, by the network device, first information sent by the terminaldevice; and determining, by the network device, a first downlinktransmission beam group from the plurality of downlink transmission beamgroups according to the first information, at least one of the pluralityof downlink transmission beam groups including a plurality of downlinktransmission beams.

In a possible implementation manner, the first information is a randomaccess preamble sequence, and the determining, by the network device,the first downlink transmission beam group from the plurality ofdownlink transmission beam groups according to the first information,includes: determining, by the network device, the first downlinktransmission beam group corresponding to the random access preamblesequence from the plurality of downlink transmission beam groups,according to the random access preamble sequence, or determining, by thenetwork device, the first downlink transmission beam group correspondingto a physical random access channel resource used to send the randomaccess preamble sequence from the plurality of downlink transmissionbeam groups, according to the physical random access channel resource,or determining, by the network device, the first downlink transmissionbeam group corresponding to both the random access preamble sequence anda physical random access channel resource used to send the random accesspreamble sequence from the plurality of downlink transmission beamgroups, according to the random access preamble sequence and thephysical random access channel resource.

In a possible implementation manner, after the network device receivesthe first information sent by the terminal device, the method furtherincludes: receiving, by the network device, second information sent bythe terminal device; and determining, by the network device, the firstdownlink transmission beam from the plurality of downlink transmissionbeam groups according to the second information, the first downlinktransmission beam being a downlink transmission beam that is expected bythe terminal device for the network device to transmit a subsequentsignal.

In a possible implementation manner, the first downlink transmissionbeam is a beam in the downlink transmission beam group, and thedetermining, by the network device, the first downlink transmission beamfrom the plurality of downlink transmission beam groups according to thesecond information, includes: determining, by the network device, thefirst downlink transmission beam from the first downlink transmissionbeam group according to the second information.

In a possible implementation manner, before the network device receivesthe second information sent by the terminal device, the method furtherincludes: sending, by the network device, third information to theterminal device, the third information being used to indicate whetherthe terminal device needs to send the second information to the networkdevice; and receiving, by the network device, the second informationsent by the terminal device, including: receiving, by the networkdevice, the second information sent by the terminal device according tothe third information.

Further, the third information is carried in a random access responsemessage sent by the network device to the terminal device, and/or thesecond information is carried in a message used to send an identifier ofthe terminal device in a random access process.

In a possible implementation manner, the second information is anidentifier of a signal carried on the first downlink transmission beamreceived by the terminal device, and the signal carried on the firstdownlink transmission beam is at least one of following signals: aprimary synchronization signal, a secondary synchronization signal, abroadcast signal, a reference signal, and a signal carrying a systemmessage.

In a third aspect, there is provided a terminal device for performingthe method in the first aspect or any of possible implementations of thefirst aspect. In particular, the terminal device includes a unit forperforming the method in the first aspect or any of the possibleimplementations of the first aspect.

In a fourth aspect, there is provided a network device for performingthe method in the second aspect or any of possible implementations ofthe first aspect. In particular, the terminal device includes a unit forperforming the method in the second aspect or any of the possibleimplementations of the second aspect.

In a fifth aspect, there is provided a terminal device. The terminaldevice includes: a memory, a processor, an input interface, and anoutput interface. The memory, the processor, the input interface, andthe output interface are connected by a bus system. The memory is usedfor storing instructions, and the processor is used to perform theinstructions stored in the memory, so as to perform the method in thefirst aspect or any of the possible implementations of the first aspectdescribed above.

In a sixth aspect, there is provided a network device. The networkdevice includes: a memory, a processor, an input interface, and anoutput interface. The memory, the processor, the input interface, andthe output interface are connected by a bus system. The memory is usedfor storing instructions, and the processor is used to perform theinstructions stored in the memory, so as to perform the method in thesecond aspect or any of the possible implementations of the secondaspect described above.

In a seventh aspect, there is provided a computer storage medium, forstoring computer software instructions used for performing the method inthe first aspect or any of the possible implementations of the firstaspect described above, or the method in the second aspect or any of thepossible implementations of the second aspect described above, includinga program designed to perform the above aspects.

These and other aspects of the present application will be more conciseand understandable from description of following embodiments.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 shows a schematic diagram of an application scenario according toan embodiment of the present application.

FIG. 2 shows a schematic block diagram of a random access methodaccording to an embodiment of the present application.

FIG. 3 shows a flowchart of a random access process.

FIG. 4 shows another schematic block diagram of a method fortransmitting a signal according to an embodiment of the presentapplication.

FIG. 5 shows a schematic block diagram of a terminal device fortransmitting a signal according to an embodiment of the presentapplication.

FIG. 6 shows a schematic block diagram of a network device fortransmitting a signal according to an embodiment of the presentapplication.

FIG. 7 shows another schematic block diagram of a terminal device fortransmitting a signal according to an embodiment of the presentapplication.

FIG. 8 shows another schematic block diagram of a network device fortransmitting a signal according to an embodiment of the presentapplication.

DETAILED DESCRIPTION

Technical solutions in embodiments of the present application will beclearly and completely described below with reference to drawings in theembodiments of the present application.

It should be understood that the technical solutions in the embodimentsof the present application may be applied to various communicationsystems, for example, Global System of Mobile communication (GSM)system, Code Division Multiple Access (CDMA) system, Wideband CodeDivision Multiple Access (WCDMA) system, General Packet Radio Service(GPRS), Long Term Evolution (LTE) system, LTE Frequency Division Duplex(FDD) system, LTE Time Division Duplex (TDD), Universal MobileTelecommunication System (UMTS), Worldwide Interoperability forMicrowave Access (WiMAX) communication system or future 5G system, andthe like.

In particular, the technical solutions in the embodiments of the presentapplication may be applied to various communication systems based onnon-orthogonal multiple access technology, such as Sparse Code MultipleAccess (SCMA) system, Low Density Signature (LDS) system, and the like,and the SCMA system and the LDS system may also be referred to as othernames in the field of communication; further, the technical solutions inthe embodiments of the present application may be applied to amulti-carrier transmission system adopting a non-orthogonal multipleaccess technology, for example, Orthogonal Frequency DivisionMultiplexing (OFDM), Filter Bank Multi-Carrier (FBMC), GeneralizedFrequency Division Multiplexing (GFDM), Filtered-OFDM (F-OFDM) system,and the like adopting the non-orthogonal multiple access technology.

The terminal device in the embodiments of the present application mayrefer to User Equipment (UE), an access terminal, a user unit, a userstation, a mobile station, a mobile platform, a remote station, a remoteterminal, a mobile device, a user terminal, a terminal, a wirelesscommunication device, a user agent or a user device. The access terminalmay be a cellular phone, a cordless phone, a Session Initiation Protocol(SIP) phone, a Wireless Local Loop (WLL) station, a Personal DigitalAssistant (PDA), a handheld device with wireless communicationcapability, a computing device or other processing devices connected toa wireless modem, an in-vehicle device, a wearable device, a terminaldevice in a future 5G network or a terminal device in future Public LandMobile Network (PLMN), and the like, which is not limited in theembodiments of the present application.

The network device in the embodiments of the present application may bea device for communicating with a terminal device. The network devicemay be a Base Transceiver Station (BTS) in GSM or CDMA, or may be aNodeB (NB) in a WCDMA system, or may be an Evolutional NodeB (eNB oreNodeB) in the LTE system, or may be a wireless controller in a CloudRadio Access Network (CRAN) scenario, or the network device may be arelay station, an access point, an in-vehicle device, a wearable device,a network device in a future 5G network or a network device in a futureevolved PLMN network, and the like, which is not limited in theembodiments of the present application.

FIG. 1 is a schematic diagram showing an application scenario accordingto an embodiment of the present application. A communication system inFIG. 1 may include a terminal device 10 and a network device 20. Thenetwork device 20 is configured to provide communication service for theterminal device 10 and access a core network. The terminal device 10accesses the network by searching for a synchronization signal, abroadcast signal, and the like sent by the network device 20, therebyperforming communication with the network. The arrows shown in FIG. 1may represent uplink/downlink transmissions by a cellular link betweenthe terminal device 10 and the network device 20.

The communication system in FIG. 1 may adopt multi-beam technology.Specifically, for a downlink, the network device may have a plurality ofDownlink Transmit Beams (DL Tx Beam), and the terminal device may have aplurality of Downlink Receive Beams (DL Rx Beam); and for a uplink, theterminal device may have a plurality of Uplink Transmit Beams (UL TxBeam), and the network device may have a plurality of Uplink ReceiveBeams (UL Rx Beam).

Generally, since the network device does not know which downlinktransmission beams have better performance, in order to improve gain ofthe signal, the network device uses each downlink transmission beam ofall downlink transmission beams to send a downlink signal to theterminal device. For example, the network device may send D1 downlinksignals to the terminal device by using D1 downlink transmit beams, andthe terminal device may receive D1 downlink signals by using D1 downlinkreceive beams. As a result, the overhead of system signaling isrelatively large, especially in the case where the number of downlinktransmission beams is large.

Specifically, FIG. 2 shows a schematic block diagram of a random accessmethod 100 according to an embodiment of the present application. Themethod 100 may be applied to the wireless communication system shown inFIG. 1, which is not limited in the embodiments of the presentapplication. The method 100 includes the following steps.

In step S110, a terminal device receives a signal sent by a networkdevice by using a plurality of downlink transmission beam groups.

In step S120, the terminal device sends first information to the networkdevice, so that the network device determines a first downlinktransmission beam group from the plurality of downlink transmission beamgroups, at least one of the plurality of downlink transmission beamgroups including a plurality of downlink transmission beams.

Specifically, in order to reduce the overhead of system signaling, allthe downlink transmission beams may be grouped, and the terminal devicemay select a better downlink transmission beam by measuring signals ofall received downlink transmission beams, and feed back to the networkdevice by using transmission characteristic corresponding to thedownlink transmission beam, so that the network device may determinewhich group of downlink transmission beams the terminal expects foraccording to the received transmission characteristic, and may only usea part of the downlink transmission beams for signal transmission later,which reduces the overhead of system signaling.

It should be understood that a beam is physically invisible to theterminal device in a system. After receiving the signal sent by thenetwork device by a plurality of beams, the terminal device may identifydifference of the beams by using difference of signals. That is to say,the terminal device may feed back to the network device by using thetransmission characteristic indicated by a certain signal, and thenetwork device may determine which downlink transmission beam group ispreferable according to the transmission characteristic fed back by theterminal device.

Optionally, the network device may group the downlink transmission beamsin the system according to certain criteria, such as the number ofterminal devices in different downlink transmission beams, and thegrouped downlink transmission beams may be recorded as a beam group 1, abeam group 2 . . . and a beam group N, where, each beam group mayinclude one or more downlink transmission beams. After receiving thesignal sent by the network device according to the plurality of beams,the terminal device may select one or more signals by measurement, forexample, the selected signal may be a signal with better performance,and the terminal device indicates the selected beam group to the networkdevice by using the transmission characteristic indicated by the signal.For example, the terminal device may receive a system message that issent by using the plurality of beams, and each system message indicatesa random access preamble sequence corresponding to the adopted beam,where, if the random access preamble sequences corresponding to thebeams in the same beam group are the same, the terminal device mayinitiate random access to the network device according to the randomaccess preamble sequence indicated by the selected signal. The networkdevice may determine which beam group has better performance accordingto the received random access preamble sequence, and use this beam groupas a reference to send a subsequent signal to the terminal device.

It should be understood that the random access preamble sequence onlyserves as an identifier of the beam group, and other transmissioncharacteristics may also be used. Those skilled in the art understandthat several bits may be used to explicitly indicate the selected beamgroup, and the number of the bits is related to the number of the beamgroups. For example, if there are 8 beam groups, then 3 bits may be usedto indicate the beam groups, for example, it is possible to configure000 as a beam group 0, configure 0001 as a beam group 1, and so on. Theforegoing is merely an example, and the embodiments of the presentapplication are not limited thereto.

Optionally, in the embodiments of the present application, the firstinformation is a random access preamble sequence, and the random accesspreamble sequence and/or a physical random access channel resource usedto send the random access preamble sequence correspond to the firstdownlink transmission beam group.

Specifically, the network device may send the system message to theterminal device by using a plurality of downlink transmission beams, andthe system messages carried on the beams of the same beam group mayindicate the same random access preamble sequence and/or the samephysical random access channel resource. Similarly, system messagescarried on beams of different beam groups may indicate different randomaccess preamble sequences and/or different physical random accesschannel resources. Next, the terminal device initiates random access tothe network device by using a random access preamble sequence and/or aphysical random access channel resource indicated by the system messagecarried on the selected downlink transmission beam. The network devicemay determine, according to received random access preamble sequence orreceived physical random access channel resource, which one of thedownlink transmission beam groups is selected by the terminal device.

The random access technology is the primary content of communicationbetween a terminal and a network in a mobile communication system. In awireless cellular network, the terminal initiates a connection requestto the network through a random access process. For ease ofunderstanding, the random access process will be briefly described belowwith reference to FIG. 3. As shown in FIG. 3, the random access processmainly includes following contents.

Msg1, the first is sending a random access preamble signal. The mainpurpose is that the network device may correctly estimate a transmissiondelay of the terminal device, and solve a conflict problem that aplurality of terminal devices simultaneously initiate the accessrequest.

Msg2, feedback information sent by the network device to the terminalmay include the transmission delay required for uplink synchronizationand an access overload condition of the current system. In addition, thenetwork device also feeds back the uplink resource location allocated tothe accessed terminal device to the terminal.

Msg3, the terminal device may send its own Cell Radio Network TemporaryIdentifier (C-RNTI) on the designated uplink resource.

Msg4, the network device feeds back conflict resolution information tothe terminal device terminal. At this point, the random access processmay completely solve the conflict problem caused by a multi-terminaldevice requesting to access the system at the same time.

In the case that the number of downlink transmission beams is small, thenetwork device may group the random access preamble sequence and/or thephysical random access channel resource according to the number ofdownlink transmission beams. The random access preamble sequence and/orthe physical random access channel resource indicated by the systemmessage transmitted on different downlink transmission beams aredifferent. If the terminal device recommends a certain downlinktransmission beam, random access is performed according to thecorresponding indication. For example, a corresponding random accesspreamble sequence is sent to the network device or the correspondingphysical random access channel resource is used to send the randomaccess preamble sequence, that is, the network device may completelydetermine the downlink transmission beam selected by the terminal devicethrough Msg1 in FIG. 3.

In the case that the number of downlink transmission beams is large, ifthe foregoing division manner is adopted, the division granularity ofthe random access preamble sequence and/or the physical random accesschannel resource is small, which may cause an increase in random accesscollision. In order to reduce the probability of the random accesscollision, the network device groups the random access preamble sequenceand/or the physical random access channel resource according to thenumber of divided downlink transmission beam groups, the random accesspreamble sequence and/or the physical random access channel resourcesindicated by the system message transmitted on different downlinktransmission beam groups are different, and the random access preamblesequence and/or the physical random access channel resource indicated bythe system message transmitted on the beam of the same downlinktransmission beam group are the same. Similarly, if the terminal devicerecommends a certain downlink transmission beam, random access isperformed according to its corresponding indication. For example, acorresponding random access preamble sequence is sent to the networkdevice or the corresponding physical random access channel resource isused to send the random access preamble sequence, that is, the networkdevice may determine the downlink transmission beam group selected bythe terminal device through Msg1 in FIG. 3.

Further, after the terminal device sends the first information to thenetwork device, the method further includes: sending, by the terminaldevice, second information to the network device, so that the networkdevice determines a first downlink transmission beam from the pluralityof downlink transmission beam groups, the first downlink transmissionbeam being a downlink transmission beam that is expected by the terminaldevice for the network device to transmit a subsequent signal.

After the terminal device indicates the selected certain downlinktransmission beam group to the network device, the terminal device maycarry information indicating the certain downlink transmission beamselected by the terminal device in the next uplink message. Thoseskilled in the art understand that several bits may be used toexplicitly indicate a certain downlink transmission beam. It should beunderstood that the selected certain downlink transmission beam here maybe a beam in one of the selected certain downlink transmission beamgroups, or may be a beam in another beam group. For example, after theterminal device indicates the first downlink transmission beam group tothe network device, the terminal device may move to another place, andthe terminal device may find that the beam in other groups may bebetter, therefore, the terminal device may directly feed back to thenetwork device related information of the selected downlink transmissionbeam, and the network device may directly determine the downlinktransmission beam according to the related information of the downlinktransmission beam selected by the terminal device. If the terminaldevice feeds back a specific downlink transmission beam to the networkdevice, the downlink transmission beam is still a better beam that wasselected before, and the terminal device may further send the identifierof the beam in the downlink transmission beam group that was selectedbefore to the network device. The identifier may also be an identifierin the plurality of beams received before by the downlink transmissionbeam selected by the terminal device. For example, the terminal devicemay receive D2 downlink signals sent by the network device through D2downlink transmission beams before initiating the random access, and ifthe terminal device selects a better downlink signal in the D2 downlinksignals, the terminal device may directly feed back the identifier ofthe selected downlink signal to the network device.

It should be understood that the foregoing downlink signal may be aprimary synchronization signal, a secondary synchronization signal, abroadcast signal, a reference signal, a signal carrying a systemmessage, or some other new signals, or may be a combination of varioussignals, which is not limited in the embodiments of the presentapplication.

It should also be understood that the second information may be carriedin the Msg3 of FIG. 3, or may be carried in any uplink message after therandom access succeeds. If the second information is carried in the Msg3in FIG. 3, the network device may also send a random access responsemessage to the terminal device by adopting all or part of the beams inthe first downlink transmission beam group recommended by the terminaldevice, and after receiving the random access response message, theterminal device may further send the Msg3 to the network device, theMsg3 carrying the second information.

Specifically, after receiving the first information sent by the terminaldevice, the network device may further send third information to theterminal device, the third information specifically indicating whetherthe terminal device needs to send the second information. For example,one bit may be carried in a certain downlink message after the randomaccess, where 0 may mean that the second information needs to be sent,and 1 may mean that the second information does not need to be sent. Itis described only in this example, which is not limited in theembodiments of the present application.

Optionally, the third information may be carried in the Msg2 in FIG. 3,that is, in a random access response message.

It should also be understood that the downlink transmission beam groupand the downlink transmission beam indicated by the terminal device areonly used as a reference for sending signals by the network device, andthe network device does not necessarily send signals by using thedownlink transmission beam group or the downlink transmission beamselected by the terminal device. In addition, after determining acertain downlink transmission beam group, the network device may notrequire the terminal device to further feed back the downlinktransmission beam with the best performance in the downlink transmissionbeam group, and may directly adopt all or part of the beams in the groupfor downlink transmission.

FIG. 4 shows a schematic block diagram of a method 200 for transmittinga signal according to an embodiment of the present application. Themethod 200 may be applied to the wireless communication system shown inFIG. 1, which is not limited in the embodiments of the presentapplication. The method 200 includes following steps.

In step 210, a network device sends a signal to a terminal device byusing a plurality of downlink transmission beam groups.

In step 220, the network device receives first information sent by theterminal device.

In step 230, the network device determines a first downlink transmissionbeam group from the plurality of downlink transmission beam groupsaccording to the first information, at least one of the plurality ofdownlink transmission beam groups including a plurality of downlinktransmission beams.

Therefore, the method for transmitting a signal in the embodiments ofthe present application can reduce system signaling overhead.

Optionally, in the embodiments of the present application, the firstinformation is a preamble sequence of random access (a random accesspreamble sequence), the determining, by the network device, the firstdownlink transmission beam group from the plurality of downlinktransmission beam groups according to the first information, includes:determining, by the network device, the first downlink transmission beamgroup corresponding to the preamble sequence of random access from theplurality of downlink transmission beam groups, according to thepreamble sequence of random access, or determining, by the networkdevice, the first downlink transmission beam group corresponding to achannel resource of physical random access (a physical random accesschannel resource) used to send the preamble sequence of random accessfrom the plurality of downlink transmission beam groups, according tothe channel resource of physical random access, or determining, by thenetwork device, the first downlink transmission beam group correspondingto both the preamble sequence of random access and the channel resourceof physical random access used to send the preamble sequence of randomaccess from the plurality of downlink transmission beam groups,according to the preamble sequence of random access and the channelresource of physical random access.

In the case that the number of downlink transmission beams is large, thenetwork device groups the random access preamble sequence and/or thephysical random access channel resource according to the number ofdivided downlink transmission beam groups, the random access preamblesequence and/or the physical random access channel resources indicatedby the system message transmitted on different downlink transmissionbeam groups are different, and the random access preamble sequenceand/or the physical random access channel resource indicated by thesystem message transmitted on the beam of the same downlink transmissionbeam group are the same. Therefore, the probability of random accesscollision can be reduced.

Optionally, in the embodiments of the present application, after thenetwork device receives the first information sent by the terminaldevice, the method further includes: receiving, by the network device,second information sent by the terminal device; and determining, by thenetwork device, the first downlink transmission beam from the pluralityof downlink transmission beam groups according to the secondinformation, the first downlink transmission beam being a downlinktransmission beam that is expected by the terminal device for thenetwork device to transmit a subsequent signal.

Optionally, in the embodiments of the present application, the firstdownlink transmission beam is a beam in the downlink transmission beamgroup, and the determining, by the network device, the first downlinktransmission beam from the plurality of downlink transmission beamgroups according to the second information, includes: determining, bythe network device, the first downlink transmission beam from the firstdownlink transmission beam group according to the first information andthe second information.

Optionally, in the embodiments of the present application, before thenetwork device receives the second information sent by the terminaldevice, the method further includes: sending, by the network device,third information to the terminal device, the third information beingused to indicate whether the terminal needs to send the secondinformation to the network device; and receiving, by the network device,the second information sent by the terminal device, includes: receiving,by the network device, the second information sent by the terminaldevice according to the third information.

Optionally, in the embodiments of the present application, the thirdinformation is carried in a response message of random access (a randomaccess response message) sent by the network device to the terminaldevice, and/or the second information is carried in a message used tosend an identifier of the terminal device in a random access process.

Optionally, in the embodiments of the present application, the secondinformation is an identifier of a signal carried on the first downlinktransmission beam received by the terminal device, and the signalcarried on the first downlink transmission beam is at least one offollowing signals: a primary synchronization signal, a secondarysynchronization signal, a broadcast signal, a reference signal, and asignal carrying a system message.

It should be understood that the interaction between the network deviceand the terminal device and related features, functions, and the likedescribed at the network device correspond to related features andfunctions of the terminal device. That is, the network device receivesthe information that the terminal device sends to the network device. Itwill not be elaborated herein for brevity.

It should also be understood that in various embodiments of the presentapplication, the size of sequence numbers of above processes does notimply a sequence of execution orders, and the order of execution of theprocesses should be determined by its function and internal logic, whichis not limited in implementation process of the embodiments of thepresent application.

The method for transmitting a signal according to the embodiments of thepresent application is described in detail above. An apparatus fortransmitting a signal according to the embodiments of the presentapplication will be described below with reference to FIG. 5 to FIG. 8,and the technical features described in the method embodiments areapplicable to following apparatus embodiments.

FIG. 5 shows a schematic block diagram of a terminal device 300 fortransmitting a signal according to an embodiment of the presentapplication. As is shown in FIG. 5, the terminal device 300 includes afirst receiving unit 310 and a first sending unit 320.

The first receiving unit 310 is configured to receive a signal sent by anetwork device by using a plurality of downlink transmission beamgroups;

The first sending unit 320 is configured to first information to thenetwork device, so that the network device determines a first downlinktransmission beam group from the plurality of downlink transmission beamgroups, at least one of the plurality of downlink transmission beamgroups including a plurality of downlink transmission beams.

Therefore, the terminal device for transmitting a signal in theembodiments of the present application can reduce the system signalingoverhead.

Optionally, in the embodiments of the present application, the firstinformation is a preamble sequence of random access, and the preamblesequence of random access and/or channel resource of physical randomaccess used to send the preamble sequence of random access correspond tothe first downlink transmission beam group.

Optionally, in the embodiments of the present application, the terminaldevice 300 further includes: a second sending unit 330, configured tosend second information to the network device, so that the networkdevice determines a first downlink transmission beam from the pluralityof downlink transmission beam groups, the first downlink transmissionbeam being a downlink transmission beam that is expected by the terminaldevice for the network device to transmit a subsequent signal.

Optionally, in the embodiments of the present application, the firstdownlink transmission beam is a beam in the first downlink transmissionbeam group.

Optionally, in the embodiments of the present application, the terminaldevice further includes: a second receiving unit 340, configured toreceive third information sent by the network device, the thirdinformation being used to indicate whether the terminal device needs tosend the second information to the network device; and a determiningunit 350, configured to determine, according to the third information,whether to send the second information to the network device.

Optionally, in the embodiments of the present application, the thirdinformation is carried in a random access response message sent by thenetwork device to the terminal device, and/or the second information iscarried in a message used to send an identifier of the terminal devicein a random access process.

Optionally, in the embodiments of the present application, the secondinformation is an identifier of a signal carried on the first downlinktransmission beam received by the terminal device, and the signalcarried on the first downlink transmission beam is at least one offollowing signals: a primary synchronization signal, a secondarysynchronization signal, a broadcast signal, a reference signal, and asignal carrying a system message.

It should be understood that the terminal device 300 for transmittingthe signal according to the embodiments of the present application maycorrespond to the terminal device in the method embodiments of thepresent application, and the foregoing and other operations and/orfunctions of respective units in the terminal device 300 arerespectively used for implementing the corresponding processes of theterminal device in the method 100 shown in FIG. 2 and FIG. 3, and itwill not be elaborated herein again for brevity.

FIG. 6 shows a schematic block diagram of a network device 400 fortransmitting a signal according to an embodiment of the presentapplication. As shown in FIG. 6, the network device 400 includes: afirst sending unit 410, a first receiving unit 420, and a firstdetermining unit 430.

The first sending unit 410 is configured to send a signal to a terminaldevice by using a plurality of downlink transmission beam groups.

The first receiving unit 420 is configured to receive first informationsent by the terminal device.

The first determining unit 430 is configured to determine a firstdownlink transmission beam group from the plurality of downlinktransmission beam groups according to the first information, at leastone of the plurality of downlink transmission beam groups including aplurality of downlink transmission beams.

Therefore, the terminal device for transmitting a signal in theembodiments of the present application can reduce the system signalingoverhead.

Optionally, in the embodiments of the present application, the firstinformation is a random access preamble sequence, and the firstdetermining unit 430 is specifically configured to: determine the firstdownlink transmission beam group corresponding to the random accesspreamble sequence from the plurality of downlink transmission beamgroups, according to the random access preamble sequence, or determinethe first downlink transmission beam group corresponding to a physicalrandom access channel resource used to send the random access preamblesequence, according to the physical random access channel resource, ordetermine the first downlink transmission beam group corresponding toboth the random access preamble sequence and the physical random accesschannel resource used to send the random access preamble sequence,according to the random access preamble sequence and the physical randomaccess channel resource.

Optionally, in the embodiments of the present application, the networkdevice 400 further includes: a second receiving unit 440, configured toreceive second information sent by the terminal device, the secondinformation being used to indicate the first downlink transmission beamin the plurality of downlink transmission beam groups, the firstdownlink transmission beam being a downlink transmission beam that isexpected by the terminal device for the network device to transmit asubsequent signal; and a second determining unit 450, configured todetermine the first downlink transmission beam from the plurality ofdownlink transmission beam groups according to the second information.

Optionally, in the embodiments of the present application, the firstdownlink transmission beam is a beam in the downlink transmission beamgroup, and the second determining unit 450 is specifically configuredto: determine the first downlink transmission beam from the firstdownlink transmission beam group according to the second information.

Optionally, in the embodiments of the present application, the networkdevice 400 further includes: a second sending unit 460, configured tosend third information to the terminal device, the third informationbeing used to indicate whether the terminal device needs to send thesecond information to the network device; and the second receiving unit440 is specifically configured to: receive the second information sentby the terminal device according to the third information.

Optionally, in the embodiments of the present application, the thirdinformation is carried in a random access response message sent by thenetwork device to the terminal device, and/or the second information iscarried in a message used to send an identifier of the terminal devicein a random access process.

Optionally, in the embodiments of the present application, the secondinformation is an identifier of a signal carried on the first downlinktransmission beam received by the terminal device, and the signalcarried on the first downlink transmission beam is at least one offollowing signals: a primary synchronization signal, a secondarysynchronization signal, a broadcast signal, a reference signal, and asignal carrying a system message.

It should be understood that the network device 400 for transmitting thesignal according to the embodiments of the present application maycorrespond to the network device in the method embodiments of thepresent application, and the foregoing and other operations and/orfunctions of respective units in the network device 400 are respectivelyused for implementing the corresponding processes of the network devicein the method 200 shown in FIG. 4, and it will not be elaborated hereinagain for brevity.

As is shown in FIG. 7, there is further provided a terminal device 500for transmitting a signal in the embodiment of the present application.The terminal device 500 may be the terminal device 300 in FIG. 3 thatmay be used to execute the contents of the terminal device correspondingto the method 100 in FIG. 2. The terminal device 500 includes an inputinterface 510, an output interface 520, a processor 530, and a memory540. The input interface 510, the output interface 520, the processor530, and the memory 540 may be connected by a bus system. The memory 540is configured to store programs, instructions or codes. The processor530 is configured to execute the programs, the instructions or the codesin the memory 540 to control the input interface 510 to receive asignal, control the output interface 520 to send a signal, and completeoperations in the foregoing method embodiments.

Therefore, the terminal device for transmitting a signal in theembodiments of the present application can reduce the system signalingoverhead.

It should be understood that, in the embodiments of the presentapplication, the processor 530 may be a Central Processing Unit (CPU),and the processor 530 may also be other general purpose processors,Digital Signal Processor (DSP), Application Specific Integrated Circuit(ASIC), Field-Programmable Gate Array (FPGA) or other programmable logicdevices, discrete gate or transistor logic devices, discrete hardwarecomponents, and the like. The general purpose processor may be amicroprocessor, any conventional processor or the like.

The memory 540 may include read-only memory and random access memory,and provides instructions and data to the processor 530. A portion ofthe memory 540 may also include a non-volatile random access memory. Forexample, the memory 540 may also store information of a type of adevice.

In implementation process, each content of the foregoing method may becompleted by an integrated logic circuit of hardware or an instructionin a form of software in the processor 530. The content of the methoddisclosed in the embodiments of the present application may be directlyimplemented by a hardware processor, or may be performed by acombination of hardware and software modules in the processor. Thesoftware module may be located in a conventional storage medium, such asa random access memory, a flash memory, a read only memory, aprogrammable read only memory or an electrically erasable programmablememory, a register, and the like. The storage medium is located in thememory 540, and the processor 530 reads the information in the memory540 and combines the hardware to complete the content of the abovemethod. To avoid repetition, it will not be elaborated here.

In a specific implementation, the first receiving unit 310 and thesecond receiving unit 340 in the terminal device 300 may be implementedby the input interface 510 in FIG. 7, and the first sending unit 320 andthe second sending unit 330 in the terminal device 300 may beimplemented by the output interface 520 in FIG. 7, and the determiningunit 350 in the terminal device 300 may be implemented by the processor530 in FIG. 7.

As is shown in FIG. 8, there is further provided a network device 600for transmitting a signal in the embodiment of the present application.The network device 600 may be the network device 400 in FIG. 4 that maybe used to execute the content of the network device corresponding tothe method 200 in FIG. 4. The network device 600 includes an inputinterface 610, an output interface 620, a processor 630, and a memory640. The input interface 610, the output interface 620, the processor630, and the memory 640 may be connected by a bus system. The memory 640is configured to store programs, instructions or codes. The processor630 is configured to execute programs, instructions or codes in thememory 640 to control the input interface 610 to receive a signal,control the output interface 620 to send a signal, and completeoperations in the foregoing method embodiments.

Therefore, the network device for transmitting a signal in theembodiments of the present application can reduce the system signalingoverhead.

It should be understood that, in the embodiments of the presentapplication, the processor 630 may be a Central Processing Unit (CPU),and the processor 630 may also be other general purpose processors,Digital Signal Processor (DSP), Application Specific Integrated Circuit(ASIC), Field-Programmable Gate Array (FPGA) or other programmable logicdevices, discrete gate or transistor logic devices, discrete hardwarecomponents, and the like. The general purpose processor may be amicroprocessor, any conventional processor or the like.

The memory 640 may include read-only memory and random access memory,and provides instructions and data to the processor 630. A portion ofthe memory 640 may also include a non-volatile random access memory. Forexample, the memory 640 may also store information of a type of adevice.

In implementation process, the content of the foregoing method may becompleted by an integrated logic circuit of hardware or an instructionin a form of software in the processor 630. The content of the methoddisclosed in the embodiments of the present application may be directlyimplemented by a hardware processor, or may be performed by acombination of hardware and software modules in the processor. Thesoftware module may be located in a conventional storage medium, such asa random access memory, a flash memory, a read only memory, aprogrammable read only memory or an electrically erasable programmablememory, a register, and the like. The storage medium is located in thememory 640, and the processor 630 reads the information in the memory640 and combines the hardware to complete the content of the abovemethod. To avoid repetition, it will not be elaborated here.

In a specific implementation, the first determining unit 430 and thesecond determining unit 450 in the network device 400 may be implementedby the processor 630 in FIG. 8, and the first sending unit 410 and thesecond sending unit 460 may be implemented by the output interface 620in FIG. 8, and the first receiving unit 420 and the second receivingunit 440 may be implemented by the input interface 610 in FIG. 8.

Those of ordinary skills in the art may be aware that, the units andalgorithm steps in individual examples described in combination with theembodiments described in the present disclosure may be implemented byelectronic hardware or a combination of computer software and electronichardware. Whether the functions are performed by hardware or softwaredepends on particular applications and design constraint conditions ofthe technical solutions. A person skilled in the art may use differentmethods to implement the described functions for each particularapplication, but it should not be considered that the implementationgoes beyond the scope of the present application.

It may be clearly understood by those skilled in the art that, for thepurpose of convenient and brief description, for a detailed workingprocess of the foregoing system, apparatus, and unit, reference may bemade to a corresponding process in the foregoing method embodiments, anddetails are not described herein again.

In the several embodiments provided in the present application, itshould be understood that the disclosed systems, apparatuses and methodsmay be implemented in other ways. For example, the apparatus embodimentsdescribed above are merely illustrative. For example, the division ofthe units is only a kind of logical function division. In practice,other division manner may be used. For example, a plurality of units orcomponents may be combined or integrated into another system, or somefeatures may be ignored or not performed. In addition, the illustratedor discussed mutual coupling or direct coupling or communicationconnection may be indirect coupling or communication connection throughsome interfaces, devices or units, and may be in electrical, mechanicalor other forms.

The units described as separated parts may or may not be physicallyseparated, and the parts displayed as units may or may not be physicalunits, that is, may be located in one place, or may be distributed on aplurality of network units. Some or all of the units may be selectedaccording to actual needs to achieve the objectives of the solutions inthe embodiments.

In addition, each functional unit in each embodiment of the presentapplication may be integrated in one processing unit, or each unit mayexist alone physically, or two or more units may be integrated in oneunit.

The functions may also be stored in a computer-readable storage mediumif being implemented in the form of a software functional unit and soldor used as an independent product. Based on such understanding, theessence of the technical solutions of the present application, or thepart contributing to the prior art or all or a part of the technicalsolutions, may be embodied in the form of a software product. Thecomputer software product is stored in a storage medium including anumber of instructions such that a computer device (which may be apersonal computer, a server, or a network device, etc.) performs all ora part of steps of the method described in each of the embodiments ofthe present application. The foregoing storage medium includes: anymedium that is capable of storing program codes such as a USB disk, amobile hard disk, a Read-Only Memory (ROM), a Random Access Memory(RAM), a magnetic disk or an optical disk, and the like.

The foregoing descriptions are merely detailed embodiments of thepresent application, but the protection scope of the present applicationis not limited thereto. Any person skilled in the art can easily thinkof changes or substitutions within the technical scope of the presentapplication, and all the changes or substitutions should be covered bythe protection scope of the present application. Therefore, theprotection scope of the present application should be subjected to theprotection scope of the claims.

What is claimed is:
 1. A method for transmitting a signal, comprising:receiving, by a terminal device, a signal sent by a network device byusing a plurality of downlink transmission beam groups; and sending, bythe terminal device, first information to the network device, so thatthe network device determines a first downlink transmission beam groupfrom the plurality of downlink transmission beam groups, at least one ofthe plurality of downlink transmission beam groups comprising aplurality of downlink transmission beams.
 2. The method according toclaim 1, wherein, the first information is a random access preamblesequence, and at least one of the random access preamble sequence and aphysical random access channel resource used to send the random accesspreamble sequence corresponds to the first downlink transmission beamgroup.
 3. The method according to claim 1, wherein, after sending, bythe terminal device, the first information to the network device, themethod further comprises: sending, by the terminal device, secondinformation to the network device, so that the network device determinesa first downlink transmission beam from the plurality of downlinktransmission beam groups, the first downlink transmission beam being adownlink transmission beam that is expected by the terminal device forthe network device to transmit a subsequent signal.
 4. The methodaccording to claim 3, wherein, the first downlink transmission beam is abeam in the first downlink transmission beam group.
 5. The methodaccording to claim 3, wherein, before sending, by the terminal device,the second information to the network device, the method furthercomprises: receiving, by the terminal device, third information sent bythe network device, the third information being used to indicate whetherthe terminal device needs to send the second information to the networkdevice; and determining, by the terminal device, whether to send thesecond information to the network device according to the thirdinformation.
 6. The method according to claim 5, wherein, the thirdinformation is carried in a random access response message sent by thenetwork device to the terminal device, or the second information iscarried in a message used to send an identifier of the terminal devicein a random access process, or the third information is carried in arandom access response message sent by the network device to theterminal device and the second information is carried in a message usedto send an identifier of the terminal device in a random access process.7. The method according to claim 3, wherein, the second information isan identifier of a signal carried on the first downlink transmissionbeam received by the terminal device, and the signal carried on thefirst downlink transmission beam is at least one of following signals: aprimary synchronization signal, a secondary synchronization signal, abroadcast signal, a reference signal, and a signal carrying a systemmessage.
 8. A terminal device for transmitting a signal, comprising: amemory for storing instructions; a processor for performing theinstructions stored in the memory; an input interface; and an outputinterface, wherein the memory, the processor, the input interface, andthe output interface are connected by a bus system, and the processor isconfigured to: receive, via the input interface, a signal sent by anetwork device by using a plurality of downlink transmission beamgroups; and send, via the output interface, first information to thenetwork device, so that the network device determines a first downlinktransmission beam group from the plurality of downlink transmission beamgroups, at least one of the plurality of downlink transmission beamgroups comprising a plurality of downlink transmission beams.
 9. Theterminal device according to claim 8, wherein, the first information isa random access preamble sequence, and at least one of the random accesspreamble sequence and a physical random access channel resource used tosend the random access preamble sequence corresponds to the firstdownlink transmission beam group.
 10. The terminal device according toclaim 8, wherein the processor is further configured to: send, via theoutput interface, second information to the network device, so that thenetwork device determines a first downlink transmission beam from theplurality of downlink transmission beam groups, the first downlinktransmission beam being a downlink transmission beam that is expected bythe terminal device for the network device to transmit a subsequentsignal.
 11. The terminal device according to claim 10, wherein, thefirst downlink transmission beam is a beam in the first downlinktransmission beam group.
 12. The terminal device according to claim 10,wherein the processor is further configured to: receive, via the inputinterface, third information sent by the network device, the thirdinformation being used to indicate whether the terminal device needs tosend the second information to the network device; and determine whetherto send the second information to the network device according to thethird information.
 13. The terminal device according to claim 12,wherein, the third information is carried in a random access responsemessage sent by the network device to the terminal device, or the secondinformation is carried in a message used to send an identifier of theterminal device in a random access process, or the third information iscarried in a random access response message sent by the network deviceto the terminal device and the second information is carried in amessage used to send an identifier of the terminal device in a randomaccess process.
 14. The terminal device according to claim 10, wherein,the second information is a signal identifier carried on the firstdownlink transmission beam received by the terminal device, and thesignal carried on the first downlink transmission beam is at least oneof following signals: a primary synchronization signal, a secondarysynchronization signal, a broadcast signal, a reference signal, and asignal carrying a system message.
 15. A network device for transmittinga signal, comprising: a memory for storing instructions; a processor forperforming the instructions stored in the memory; an input interface;and an output interface, wherein the memory, the processor, the inputinterface, and the output interface are connected by a bus system, andthe processor is configured to: send, via the output interface, a signalto a terminal device by using a plurality of downlink transmission beamgroups; receive, via the input interface, first information sent by theterminal device; and determine a first downlink transmission beam groupfrom the plurality of downlink transmission beam groups according to thefirst information, at least one of the plurality of downlinktransmission beam groups comprising a plurality of downlink transmissionbeams.
 16. The network device according to claim 15, wherein, the firstinformation is a random access preamble sequence, and the processor isconfigured to perform one of the following: determine the first downlinktransmission beam group corresponding to the random access preamblesequence from the plurality of downlink transmission beam groups,according to the random access preamble sequence; determine the firstdownlink transmission beam group corresponding to a physical randomaccess channel resource used to send the random access preamblesequence, according to the physical random access channel resource; anddetermine the first downlink transmission beam group corresponding toboth the random access preamble sequence and a physical random accesschannel resource used to send the random access preamble sequence,according to the random access preamble sequence and the physical randomaccess channel resource.
 17. The network device according to claim 15,wherein the processor is further configured to: receive, via the inputinterface, second information sent by the terminal device; and determinethe first downlink transmission beam from the plurality of downlinktransmission beam groups according to the second information, the firstdownlink transmission beam being a downlink transmission beam that isexpected by the terminal device for the network device to transmit asubsequent signal.
 18. The network device according to claim 17,wherein, the first downlink transmission beam is a beam in the downlinktransmission beam group, and the processor is configured to: determinethe first downlink transmission beam from the first downlinktransmission beam group according to the second information.
 19. Thenetwork device according to claim 17, wherein the processor is furtherconfigured to: send, via the output interface, third information to theterminal device, the third information being used to indicate whetherthe terminal device needs to send the second information to the networkdevice; and receive, via the input interface, the second informationsent by the terminal device according to the third information.
 20. Thenetwork device according to claim 19, wherein, the third information iscarried in a random access response message sent by the network deviceto the terminal device, or the second information is carried in amessage used to send an identifier of the terminal device in a randomaccess process, or the third information is carried in a random accessresponse message sent by the network device to the terminal device andthe second information is carried in a message used to send anidentifier of the terminal device in a random access process.